2018 Confirmed

1LT, 2LT; deleted for 2019 (GM's official 2019 change list as printed on GM Authority's 2019 changes page); the 2018 guide prints front fog lamps with chrome rings without a code, S on 1LT, ACTIV and 2LT

SS — single generation (2014–2017)

2014–2015 Factory-verified

S; deleted for 2016 (GM Authority 2016 SS changes)

GM factory document — 2014 chevrolet ss fleet order guide wayback, p.3.
GM factory document — 2015 chevrolet ss fleet order guide wayback, p.5.

Suburban — K2XX (2015–2020)

2015–2019 Factory-verified

LS: not available; LT: A, only with PCK or Z71 (2016: or PDA); 2018–2019 from GM's 2018 and 2019 Suburban order guides (GM Authority copies)

GM factory document — 2015 chevrolet suburban fleet order guide wayback, p.3.
GM factory document — 2016 chevrolet suburban fleet order guide wayback, p.3.
GM factory document — 2016 chevrolet escalade escalade esv suburban tahoe yukon yukon xl electrical body builders manual service manual 2016 en us, p.14.
GM factory document — 2017 chevrolet escalade escalade esv suburban tahoe yukon yukon xl electrical body builders manual service manual 2017 en us 1, p.32.
GM factory document — 2018 chevrolet suburban order guide copy gm authority, p.10.
GM factory document — 2019 chevrolet suburban order guide copy gm authority, p.10.

Tahoe — K2XX (2015–2020)

2015–2019 Factory-verified

LS: not available; LT: A, only with PCK or Z71 (2016: or PDA); 2018–2019 from GM's 2018 and 2019 Tahoe order guides (GM Authority copies)

GM factory document — 2015 chevrolet tahoe fleet order guide wayback, p.4.
GM factory document — 2016 chevrolet tahoe fleet order guide wayback, p.3.
GM factory document — 2016 chevrolet escalade escalade esv suburban tahoe yukon yukon xl electrical body builders manual service manual 2016 en us, p.14.
GM factory document — 2017 chevrolet escalade escalade esv suburban tahoe yukon yukon xl electrical body builders manual service manual 2017 en us 1, p.32.
GM factory document — 2018 chevrolet tahoe order guide copy gm authority, p.10.
GM factory document — 2019 chevrolet tahoe order guide copy gm authority, p.10.

Traverse — C1XX (2018–2024)

2018–2019 Factory-verified

LT Cloth (2FL), LT Cloth, LT Leather, RS, Premier, High Country: S

GM factory document — 2018 chevrolet traverse order guide copy gm authority, p.14, p.51.
GM factory document — 2019 chevrolet traverse order guide copy gm authority, p.17, p.73.

Trax — first US generation (2015–2022)

2016, 2018–2019 Factory-verified

LTZ (2016), Premier (2018–2019): S

GM factory document — 2016 chevrolet trax fleet order guide wayback, p.3.
GM factory document — 2018 chevrolet trax order guide copy gm authority, p.19.
GM factory document — 2019 chevrolet trax order guide copy gm authority, p.19.

This page aggregates every documented appearance of T3U in the Chevrolet reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.